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42 * The mbuf library provides the ability to create and destroy buffers
43 * that may be used by the RTE application to store message
44 * buffers. The message buffers are stored in a mempool, using the
45 * RTE mempool library.
47 * This library provide an API to allocate/free packet mbufs, which are
48 * used to carry network packets.
50 * To understand the concepts of packet buffers or mbufs, you
51 * should read "TCP/IP Illustrated, Volume 2: The Implementation,
52 * Addison-Wesley, 1995, ISBN 0-201-63354-X from Richard Stevens"
53 * http://www.kohala.com/start/tcpipiv2.html
57 #include <rte_common.h>
58 #include <rte_mempool.h>
59 #include <rte_memory.h>
60 #include <rte_atomic.h>
61 #include <rte_prefetch.h>
62 #include <rte_branch_prediction.h>
63 #include <rte_mbuf_ptype.h>
70 * Packet Offload Features Flags. It also carry packet type information.
71 * Critical resources. Both rx/tx shared these bits. Be cautious on any change
73 * - RX flags start at bit position zero, and get added to the left of previous
75 * - The most-significant 3 bits are reserved for generic mbuf flags
76 * - TX flags therefore start at bit position 60 (i.e. 63-3), and new flags get
77 * added to the right of the previously defined flags i.e. they should count
78 * downwards, not upwards.
80 * Keep these flags synchronized with rte_get_rx_ol_flag_name() and
81 * rte_get_tx_ol_flag_name().
85 * RX packet is a 802.1q VLAN packet. This flag was set by PMDs when
86 * the packet is recognized as a VLAN, but the behavior between PMDs
87 * was not the same. This flag is kept for some time to avoid breaking
88 * applications and should be replaced by PKT_RX_VLAN_STRIPPED.
90 #define PKT_RX_VLAN_PKT (1ULL << 0)
92 #define PKT_RX_RSS_HASH (1ULL << 1) /**< RX packet with RSS hash result. */
93 #define PKT_RX_FDIR (1ULL << 2) /**< RX packet with FDIR match indicate. */
97 * Checking this flag alone is deprecated: check the 2 bits of
98 * PKT_RX_L4_CKSUM_MASK.
99 * This flag was set when the L4 checksum of a packet was detected as
100 * wrong by the hardware.
102 #define PKT_RX_L4_CKSUM_BAD (1ULL << 3)
106 * Checking this flag alone is deprecated: check the 2 bits of
107 * PKT_RX_IP_CKSUM_MASK.
108 * This flag was set when the IP checksum of a packet was detected as
109 * wrong by the hardware.
111 #define PKT_RX_IP_CKSUM_BAD (1ULL << 4)
113 #define PKT_RX_EIP_CKSUM_BAD (1ULL << 5) /**< External IP header checksum error. */
116 * A vlan has been stripped by the hardware and its tci is saved in
117 * mbuf->vlan_tci. This can only happen if vlan stripping is enabled
118 * in the RX configuration of the PMD.
120 #define PKT_RX_VLAN_STRIPPED (1ULL << 6)
123 * Mask of bits used to determine the status of RX IP checksum.
124 * - PKT_RX_IP_CKSUM_UNKNOWN: no information about the RX IP checksum
125 * - PKT_RX_IP_CKSUM_BAD: the IP checksum in the packet is wrong
126 * - PKT_RX_IP_CKSUM_GOOD: the IP checksum in the packet is valid
127 * - PKT_RX_IP_CKSUM_NONE: the IP checksum is not correct in the packet
128 * data, but the integrity of the IP header is verified.
130 #define PKT_RX_IP_CKSUM_MASK ((1ULL << 4) | (1ULL << 7))
132 #define PKT_RX_IP_CKSUM_UNKNOWN 0
133 #define PKT_RX_IP_CKSUM_BAD (1ULL << 4)
134 #define PKT_RX_IP_CKSUM_GOOD (1ULL << 7)
135 #define PKT_RX_IP_CKSUM_NONE ((1ULL << 4) | (1ULL << 7))
138 * Mask of bits used to determine the status of RX L4 checksum.
139 * - PKT_RX_L4_CKSUM_UNKNOWN: no information about the RX L4 checksum
140 * - PKT_RX_L4_CKSUM_BAD: the L4 checksum in the packet is wrong
141 * - PKT_RX_L4_CKSUM_GOOD: the L4 checksum in the packet is valid
142 * - PKT_RX_L4_CKSUM_NONE: the L4 checksum is not correct in the packet
143 * data, but the integrity of the L4 data is verified.
145 #define PKT_RX_L4_CKSUM_MASK ((1ULL << 3) | (1ULL << 8))
147 #define PKT_RX_L4_CKSUM_UNKNOWN 0
148 #define PKT_RX_L4_CKSUM_BAD (1ULL << 3)
149 #define PKT_RX_L4_CKSUM_GOOD (1ULL << 8)
150 #define PKT_RX_L4_CKSUM_NONE ((1ULL << 3) | (1ULL << 8))
152 #define PKT_RX_IEEE1588_PTP (1ULL << 9) /**< RX IEEE1588 L2 Ethernet PT Packet. */
153 #define PKT_RX_IEEE1588_TMST (1ULL << 10) /**< RX IEEE1588 L2/L4 timestamped packet.*/
154 #define PKT_RX_FDIR_ID (1ULL << 13) /**< FD id reported if FDIR match. */
155 #define PKT_RX_FDIR_FLX (1ULL << 14) /**< Flexible bytes reported if FDIR match. */
158 * The 2 vlans have been stripped by the hardware and their tci are
159 * saved in mbuf->vlan_tci (inner) and mbuf->vlan_tci_outer (outer).
160 * This can only happen if vlan stripping is enabled in the RX
161 * configuration of the PMD. If this flag is set, PKT_RX_VLAN_STRIPPED
164 #define PKT_RX_QINQ_STRIPPED (1ULL << 15)
168 * RX packet with double VLAN stripped.
169 * This flag is replaced by PKT_RX_QINQ_STRIPPED.
171 #define PKT_RX_QINQ_PKT PKT_RX_QINQ_STRIPPED
174 * When packets are coalesced by a hardware or virtual driver, this flag
175 * can be set in the RX mbuf, meaning that the m->tso_segsz field is
176 * valid and is set to the segment size of original packets.
178 #define PKT_RX_LRO (1ULL << 16)
180 /* add new RX flags here */
182 /* add new TX flags here */
185 * Bits 45:48 used for the tunnel type.
186 * When doing Tx offload like TSO or checksum, the HW needs to configure the
187 * tunnel type into the HW descriptors.
189 #define PKT_TX_TUNNEL_VXLAN (0x1ULL << 45)
190 #define PKT_TX_TUNNEL_GRE (0x2ULL << 45)
191 #define PKT_TX_TUNNEL_IPIP (0x3ULL << 45)
192 #define PKT_TX_TUNNEL_GENEVE (0x4ULL << 45)
193 /* add new TX TUNNEL type here */
194 #define PKT_TX_TUNNEL_MASK (0xFULL << 45)
197 * Second VLAN insertion (QinQ) flag.
199 #define PKT_TX_QINQ_PKT (1ULL << 49) /**< TX packet with double VLAN inserted. */
202 * TCP segmentation offload. To enable this offload feature for a
203 * packet to be transmitted on hardware supporting TSO:
204 * - set the PKT_TX_TCP_SEG flag in mbuf->ol_flags (this flag implies
206 * - set the flag PKT_TX_IPV4 or PKT_TX_IPV6
207 * - if it's IPv4, set the PKT_TX_IP_CKSUM flag and write the IP checksum
209 * - fill the mbuf offload information: l2_len, l3_len, l4_len, tso_segsz
210 * - calculate the pseudo header checksum without taking ip_len in account,
211 * and set it in the TCP header. Refer to rte_ipv4_phdr_cksum() and
212 * rte_ipv6_phdr_cksum() that can be used as helpers.
214 #define PKT_TX_TCP_SEG (1ULL << 50)
216 #define PKT_TX_IEEE1588_TMST (1ULL << 51) /**< TX IEEE1588 packet to timestamp. */
219 * Bits 52+53 used for L4 packet type with checksum enabled: 00: Reserved,
220 * 01: TCP checksum, 10: SCTP checksum, 11: UDP checksum. To use hardware
221 * L4 checksum offload, the user needs to:
222 * - fill l2_len and l3_len in mbuf
223 * - set the flags PKT_TX_TCP_CKSUM, PKT_TX_SCTP_CKSUM or PKT_TX_UDP_CKSUM
224 * - set the flag PKT_TX_IPV4 or PKT_TX_IPV6
225 * - calculate the pseudo header checksum and set it in the L4 header (only
226 * for TCP or UDP). See rte_ipv4_phdr_cksum() and rte_ipv6_phdr_cksum().
227 * For SCTP, set the crc field to 0.
229 #define PKT_TX_L4_NO_CKSUM (0ULL << 52) /**< Disable L4 cksum of TX pkt. */
230 #define PKT_TX_TCP_CKSUM (1ULL << 52) /**< TCP cksum of TX pkt. computed by NIC. */
231 #define PKT_TX_SCTP_CKSUM (2ULL << 52) /**< SCTP cksum of TX pkt. computed by NIC. */
232 #define PKT_TX_UDP_CKSUM (3ULL << 52) /**< UDP cksum of TX pkt. computed by NIC. */
233 #define PKT_TX_L4_MASK (3ULL << 52) /**< Mask for L4 cksum offload request. */
236 * Offload the IP checksum in the hardware. The flag PKT_TX_IPV4 should
237 * also be set by the application, although a PMD will only check
239 * - set the IP checksum field in the packet to 0
240 * - fill the mbuf offload information: l2_len, l3_len
242 #define PKT_TX_IP_CKSUM (1ULL << 54)
245 * Packet is IPv4. This flag must be set when using any offload feature
246 * (TSO, L3 or L4 checksum) to tell the NIC that the packet is an IPv4
247 * packet. If the packet is a tunneled packet, this flag is related to
250 #define PKT_TX_IPV4 (1ULL << 55)
253 * Packet is IPv6. This flag must be set when using an offload feature
254 * (TSO or L4 checksum) to tell the NIC that the packet is an IPv6
255 * packet. If the packet is a tunneled packet, this flag is related to
258 #define PKT_TX_IPV6 (1ULL << 56)
260 #define PKT_TX_VLAN_PKT (1ULL << 57) /**< TX packet is a 802.1q VLAN packet. */
263 * Offload the IP checksum of an external header in the hardware. The
264 * flag PKT_TX_OUTER_IPV4 should also be set by the application, alto ugh
265 * a PMD will only check PKT_TX_IP_CKSUM. The IP checksum field in the
266 * packet must be set to 0.
267 * - set the outer IP checksum field in the packet to 0
268 * - fill the mbuf offload information: outer_l2_len, outer_l3_len
270 #define PKT_TX_OUTER_IP_CKSUM (1ULL << 58)
273 * Packet outer header is IPv4. This flag must be set when using any
274 * outer offload feature (L3 or L4 checksum) to tell the NIC that the
275 * outer header of the tunneled packet is an IPv4 packet.
277 #define PKT_TX_OUTER_IPV4 (1ULL << 59)
280 * Packet outer header is IPv6. This flag must be set when using any
281 * outer offload feature (L4 checksum) to tell the NIC that the outer
282 * header of the tunneled packet is an IPv6 packet.
284 #define PKT_TX_OUTER_IPV6 (1ULL << 60)
286 #define __RESERVED (1ULL << 61) /**< reserved for future mbuf use */
288 #define IND_ATTACHED_MBUF (1ULL << 62) /**< Indirect attached mbuf */
290 /* Use final bit of flags to indicate a control mbuf */
291 #define CTRL_MBUF_FLAG (1ULL << 63) /**< Mbuf contains control data */
293 /** Alignment constraint of mbuf private area. */
294 #define RTE_MBUF_PRIV_ALIGN 8
297 * Get the name of a RX offload flag
300 * The mask describing the flag.
302 * The name of this flag, or NULL if it's not a valid RX flag.
304 const char *rte_get_rx_ol_flag_name(uint64_t mask);
307 * Dump the list of RX offload flags in a buffer
310 * The mask describing the RX flags.
314 * The length of the buffer.
316 * 0 on success, (-1) on error.
318 int rte_get_rx_ol_flag_list(uint64_t mask, char *buf, size_t buflen);
321 * Get the name of a TX offload flag
324 * The mask describing the flag. Usually only one bit must be set.
325 * Several bits can be given if they belong to the same mask.
326 * Ex: PKT_TX_L4_MASK.
328 * The name of this flag, or NULL if it's not a valid TX flag.
330 const char *rte_get_tx_ol_flag_name(uint64_t mask);
333 * Dump the list of TX offload flags in a buffer
336 * The mask describing the TX flags.
340 * The length of the buffer.
342 * 0 on success, (-1) on error.
344 int rte_get_tx_ol_flag_list(uint64_t mask, char *buf, size_t buflen);
347 * Some NICs need at least 2KB buffer to RX standard Ethernet frame without
348 * splitting it into multiple segments.
349 * So, for mbufs that planned to be involved into RX/TX, the recommended
350 * minimal buffer length is 2KB + RTE_PKTMBUF_HEADROOM.
352 #define RTE_MBUF_DEFAULT_DATAROOM 2048
353 #define RTE_MBUF_DEFAULT_BUF_SIZE \
354 (RTE_MBUF_DEFAULT_DATAROOM + RTE_PKTMBUF_HEADROOM)
356 /* define a set of marker types that can be used to refer to set points in the
359 typedef void *MARKER[0]; /**< generic marker for a point in a structure */
361 typedef uint8_t MARKER8[0]; /**< generic marker with 1B alignment */
363 typedef uint64_t MARKER64[0]; /**< marker that allows us to overwrite 8 bytes
364 * with a single assignment */
367 * The generic rte_mbuf, containing a packet mbuf.
372 void *buf_addr; /**< Virtual address of segment buffer. */
373 phys_addr_t buf_physaddr; /**< Physical address of segment buffer. */
375 uint16_t buf_len; /**< Length of segment buffer. */
377 /* next 6 bytes are initialised on RX descriptor rearm */
382 * 16-bit Reference counter.
383 * It should only be accessed using the following functions:
384 * rte_mbuf_refcnt_update(), rte_mbuf_refcnt_read(), and
385 * rte_mbuf_refcnt_set(). The functionality of these functions (atomic,
386 * or non-atomic) is controlled by the CONFIG_RTE_MBUF_REFCNT_ATOMIC
391 rte_atomic16_t refcnt_atomic; /**< Atomically accessed refcnt */
392 uint16_t refcnt; /**< Non-atomically accessed refcnt */
394 uint8_t nb_segs; /**< Number of segments. */
395 uint8_t port; /**< Input port. */
397 uint64_t ol_flags; /**< Offload features. */
399 /* remaining bytes are set on RX when pulling packet from descriptor */
400 MARKER rx_descriptor_fields1;
403 * The packet type, which is the combination of outer/inner L2, L3, L4
404 * and tunnel types. The packet_type is about data really present in the
405 * mbuf. Example: if vlan stripping is enabled, a received vlan packet
406 * would have RTE_PTYPE_L2_ETHER and not RTE_PTYPE_L2_VLAN because the
407 * vlan is stripped from the data.
411 uint32_t packet_type; /**< L2/L3/L4 and tunnel information. */
413 uint32_t l2_type:4; /**< (Outer) L2 type. */
414 uint32_t l3_type:4; /**< (Outer) L3 type. */
415 uint32_t l4_type:4; /**< (Outer) L4 type. */
416 uint32_t tun_type:4; /**< Tunnel type. */
417 uint32_t inner_l2_type:4; /**< Inner L2 type. */
418 uint32_t inner_l3_type:4; /**< Inner L3 type. */
419 uint32_t inner_l4_type:4; /**< Inner L4 type. */
423 uint32_t pkt_len; /**< Total pkt len: sum of all segments. */
424 uint16_t data_len; /**< Amount of data in segment buffer. */
425 /** VLAN TCI (CPU order), valid if PKT_RX_VLAN_STRIPPED is set. */
429 uint32_t rss; /**< RSS hash result if RSS enabled */
438 /**< Second 4 flexible bytes */
441 /**< First 4 flexible bytes or FD ID, dependent on
442 PKT_RX_FDIR_* flag in ol_flags. */
443 } fdir; /**< Filter identifier if FDIR enabled */
447 } sched; /**< Hierarchical scheduler */
448 uint32_t usr; /**< User defined tags. See rte_distributor_process() */
449 } hash; /**< hash information */
451 uint32_t seqn; /**< Sequence number. See also rte_reorder_insert() */
453 /** Outer VLAN TCI (CPU order), valid if PKT_RX_QINQ_STRIPPED is set. */
454 uint16_t vlan_tci_outer;
456 /* second cache line - fields only used in slow path or on TX */
457 MARKER cacheline1 __rte_cache_min_aligned;
461 void *userdata; /**< Can be used for external metadata */
462 uint64_t udata64; /**< Allow 8-byte userdata on 32-bit */
465 struct rte_mempool *pool; /**< Pool from which mbuf was allocated. */
466 struct rte_mbuf *next; /**< Next segment of scattered packet. */
468 /* fields to support TX offloads */
471 uint64_t tx_offload; /**< combined for easy fetch */
475 /**< L2 (MAC) Header Length for non-tunneling pkt.
476 * Outer_L4_len + ... + Inner_L2_len for tunneling pkt.
478 uint64_t l3_len:9; /**< L3 (IP) Header Length. */
479 uint64_t l4_len:8; /**< L4 (TCP/UDP) Header Length. */
480 uint64_t tso_segsz:16; /**< TCP TSO segment size */
482 /* fields for TX offloading of tunnels */
483 uint64_t outer_l3_len:9; /**< Outer L3 (IP) Hdr Length. */
484 uint64_t outer_l2_len:7; /**< Outer L2 (MAC) Hdr Length. */
486 /* uint64_t unused:8; */
490 /** Size of the application private data. In case of an indirect
491 * mbuf, it stores the direct mbuf private data size. */
494 /** Timesync flags for use with IEEE1588. */
496 } __rte_cache_aligned;
499 * Prefetch the first part of the mbuf
501 * The first 64 bytes of the mbuf corresponds to fields that are used early
502 * in the receive path. If the cache line of the architecture is higher than
503 * 64B, the second part will also be prefetched.
506 * The pointer to the mbuf.
509 rte_mbuf_prefetch_part1(struct rte_mbuf *m)
511 rte_prefetch0(&m->cacheline0);
515 * Prefetch the second part of the mbuf
517 * The next 64 bytes of the mbuf corresponds to fields that are used in the
518 * transmit path. If the cache line of the architecture is higher than 64B,
519 * this function does nothing as it is expected that the full mbuf is
523 * The pointer to the mbuf.
526 rte_mbuf_prefetch_part2(struct rte_mbuf *m)
528 #if RTE_CACHE_LINE_SIZE == 64
529 rte_prefetch0(&m->cacheline1);
536 static inline uint16_t rte_pktmbuf_priv_size(struct rte_mempool *mp);
539 * Return the DMA address of the beginning of the mbuf data
542 * The pointer to the mbuf.
544 * The physical address of the beginning of the mbuf data
546 static inline phys_addr_t
547 rte_mbuf_data_dma_addr(const struct rte_mbuf *mb)
549 return mb->buf_physaddr + mb->data_off;
553 * Return the default DMA address of the beginning of the mbuf data
555 * This function is used by drivers in their receive function, as it
556 * returns the location where data should be written by the NIC, taking
557 * the default headroom in account.
560 * The pointer to the mbuf.
562 * The physical address of the beginning of the mbuf data
564 static inline phys_addr_t
565 rte_mbuf_data_dma_addr_default(const struct rte_mbuf *mb)
567 return mb->buf_physaddr + RTE_PKTMBUF_HEADROOM;
571 * Return the mbuf owning the data buffer address of an indirect mbuf.
574 * The pointer to the indirect mbuf.
576 * The address of the direct mbuf corresponding to buffer_addr.
578 static inline struct rte_mbuf *
579 rte_mbuf_from_indirect(struct rte_mbuf *mi)
581 return (struct rte_mbuf *)RTE_PTR_SUB(mi->buf_addr, sizeof(*mi) + mi->priv_size);
585 * Return the buffer address embedded in the given mbuf.
588 * The pointer to the mbuf.
590 * The address of the data buffer owned by the mbuf.
593 rte_mbuf_to_baddr(struct rte_mbuf *md)
596 buffer_addr = (char *)md + sizeof(*md) + rte_pktmbuf_priv_size(md->pool);
601 * Returns TRUE if given mbuf is indirect, or FALSE otherwise.
603 #define RTE_MBUF_INDIRECT(mb) ((mb)->ol_flags & IND_ATTACHED_MBUF)
606 * Returns TRUE if given mbuf is direct, or FALSE otherwise.
608 #define RTE_MBUF_DIRECT(mb) (!RTE_MBUF_INDIRECT(mb))
611 * Private data in case of pktmbuf pool.
613 * A structure that contains some pktmbuf_pool-specific data that are
614 * appended after the mempool structure (in private data).
616 struct rte_pktmbuf_pool_private {
617 uint16_t mbuf_data_room_size; /**< Size of data space in each mbuf. */
618 uint16_t mbuf_priv_size; /**< Size of private area in each mbuf. */
621 #ifdef RTE_LIBRTE_MBUF_DEBUG
623 /** check mbuf type in debug mode */
624 #define __rte_mbuf_sanity_check(m, is_h) rte_mbuf_sanity_check(m, is_h)
626 #else /* RTE_LIBRTE_MBUF_DEBUG */
628 /** check mbuf type in debug mode */
629 #define __rte_mbuf_sanity_check(m, is_h) do { } while (0)
631 #endif /* RTE_LIBRTE_MBUF_DEBUG */
633 #ifdef RTE_MBUF_REFCNT_ATOMIC
636 * Reads the value of an mbuf's refcnt.
640 * Reference count number.
642 static inline uint16_t
643 rte_mbuf_refcnt_read(const struct rte_mbuf *m)
645 return (uint16_t)(rte_atomic16_read(&m->refcnt_atomic));
649 * Sets an mbuf's refcnt to a defined value.
656 rte_mbuf_refcnt_set(struct rte_mbuf *m, uint16_t new_value)
658 rte_atomic16_set(&m->refcnt_atomic, new_value);
662 * Adds given value to an mbuf's refcnt and returns its new value.
666 * Value to add/subtract
670 static inline uint16_t
671 rte_mbuf_refcnt_update(struct rte_mbuf *m, int16_t value)
674 * The atomic_add is an expensive operation, so we don't want to
675 * call it in the case where we know we are the uniq holder of
676 * this mbuf (i.e. ref_cnt == 1). Otherwise, an atomic
677 * operation has to be used because concurrent accesses on the
678 * reference counter can occur.
680 if (likely(rte_mbuf_refcnt_read(m) == 1)) {
681 rte_mbuf_refcnt_set(m, 1 + value);
685 return (uint16_t)(rte_atomic16_add_return(&m->refcnt_atomic, value));
688 #else /* ! RTE_MBUF_REFCNT_ATOMIC */
691 * Adds given value to an mbuf's refcnt and returns its new value.
693 static inline uint16_t
694 rte_mbuf_refcnt_update(struct rte_mbuf *m, int16_t value)
696 m->refcnt = (uint16_t)(m->refcnt + value);
701 * Reads the value of an mbuf's refcnt.
703 static inline uint16_t
704 rte_mbuf_refcnt_read(const struct rte_mbuf *m)
710 * Sets an mbuf's refcnt to the defined value.
713 rte_mbuf_refcnt_set(struct rte_mbuf *m, uint16_t new_value)
715 m->refcnt = new_value;
718 #endif /* RTE_MBUF_REFCNT_ATOMIC */
721 #define RTE_MBUF_PREFETCH_TO_FREE(m) do { \
728 * Sanity checks on an mbuf.
730 * Check the consistency of the given mbuf. The function will cause a
731 * panic if corruption is detected.
734 * The mbuf to be checked.
736 * True if the mbuf is a packet header, false if it is a sub-segment
737 * of a packet (in this case, some fields like nb_segs are not checked)
740 rte_mbuf_sanity_check(const struct rte_mbuf *m, int is_header);
743 * Allocate an unitialized mbuf from mempool *mp*.
745 * This function can be used by PMDs (especially in RX functions) to
746 * allocate an unitialized mbuf. The driver is responsible of
747 * initializing all the required fields. See rte_pktmbuf_reset().
748 * For standard needs, prefer rte_pktmbuf_alloc().
751 * The mempool from which mbuf is allocated.
753 * - The pointer to the new mbuf on success.
754 * - NULL if allocation failed.
756 static inline struct rte_mbuf *rte_mbuf_raw_alloc(struct rte_mempool *mp)
761 if (rte_mempool_get(mp, &mb) < 0)
763 m = (struct rte_mbuf *)mb;
764 RTE_ASSERT(rte_mbuf_refcnt_read(m) == 0);
765 rte_mbuf_refcnt_set(m, 1);
766 __rte_mbuf_sanity_check(m, 0);
772 * @internal Put mbuf back into its original mempool.
773 * The use of that function is reserved for RTE internal needs.
774 * Please use rte_pktmbuf_free().
777 * The mbuf to be freed.
779 static inline void __attribute__((always_inline))
780 __rte_mbuf_raw_free(struct rte_mbuf *m)
782 RTE_ASSERT(rte_mbuf_refcnt_read(m) == 0);
783 rte_mempool_put(m->pool, m);
786 /* Operations on ctrl mbuf */
789 * The control mbuf constructor.
791 * This function initializes some fields in an mbuf structure that are
792 * not modified by the user once created (mbuf type, origin pool, buffer
793 * start address, and so on). This function is given as a callback function
794 * to rte_mempool_create() at pool creation time.
797 * The mempool from which the mbuf is allocated.
799 * A pointer that can be used by the user to retrieve useful information
800 * for mbuf initialization. This pointer comes from the ``init_arg``
801 * parameter of rte_mempool_create().
803 * The mbuf to initialize.
805 * The index of the mbuf in the pool table.
807 void rte_ctrlmbuf_init(struct rte_mempool *mp, void *opaque_arg,
808 void *m, unsigned i);
811 * Allocate a new mbuf (type is ctrl) from mempool *mp*.
813 * This new mbuf is initialized with data pointing to the beginning of
814 * buffer, and with a length of zero.
817 * The mempool from which the mbuf is allocated.
819 * - The pointer to the new mbuf on success.
820 * - NULL if allocation failed.
822 #define rte_ctrlmbuf_alloc(mp) rte_pktmbuf_alloc(mp)
825 * Free a control mbuf back into its original mempool.
828 * The control mbuf to be freed.
830 #define rte_ctrlmbuf_free(m) rte_pktmbuf_free(m)
833 * A macro that returns the pointer to the carried data.
835 * The value that can be read or assigned.
840 #define rte_ctrlmbuf_data(m) ((char *)((m)->buf_addr) + (m)->data_off)
843 * A macro that returns the length of the carried data.
845 * The value that can be read or assigned.
850 #define rte_ctrlmbuf_len(m) rte_pktmbuf_data_len(m)
853 * Tests if an mbuf is a control mbuf
856 * The mbuf to be tested
858 * - True (1) if the mbuf is a control mbuf
859 * - False(0) otherwise
862 rte_is_ctrlmbuf(struct rte_mbuf *m)
864 return !!(m->ol_flags & CTRL_MBUF_FLAG);
867 /* Operations on pkt mbuf */
870 * The packet mbuf constructor.
872 * This function initializes some fields in the mbuf structure that are
873 * not modified by the user once created (origin pool, buffer start
874 * address, and so on). This function is given as a callback function to
875 * rte_mempool_create() at pool creation time.
878 * The mempool from which mbufs originate.
880 * A pointer that can be used by the user to retrieve useful information
881 * for mbuf initialization. This pointer comes from the ``init_arg``
882 * parameter of rte_mempool_create().
884 * The mbuf to initialize.
886 * The index of the mbuf in the pool table.
888 void rte_pktmbuf_init(struct rte_mempool *mp, void *opaque_arg,
889 void *m, unsigned i);
893 * A packet mbuf pool constructor.
895 * This function initializes the mempool private data in the case of a
896 * pktmbuf pool. This private data is needed by the driver. The
897 * function is given as a callback function to rte_mempool_create() at
898 * pool creation. It can be extended by the user, for example, to
899 * provide another packet size.
902 * The mempool from which mbufs originate.
904 * A pointer that can be used by the user to retrieve useful information
905 * for mbuf initialization. This pointer comes from the ``init_arg``
906 * parameter of rte_mempool_create().
908 void rte_pktmbuf_pool_init(struct rte_mempool *mp, void *opaque_arg);
911 * Create a mbuf pool.
913 * This function creates and initializes a packet mbuf pool. It is
914 * a wrapper to rte_mempool_create() with the proper packet constructor
915 * and mempool constructor.
918 * The name of the mbuf pool.
920 * The number of elements in the mbuf pool. The optimum size (in terms
921 * of memory usage) for a mempool is when n is a power of two minus one:
924 * Size of the per-core object cache. See rte_mempool_create() for
927 * Size of application private are between the rte_mbuf structure
928 * and the data buffer. This value must be aligned to RTE_MBUF_PRIV_ALIGN.
929 * @param data_room_size
930 * Size of data buffer in each mbuf, including RTE_PKTMBUF_HEADROOM.
932 * The socket identifier where the memory should be allocated. The
933 * value can be *SOCKET_ID_ANY* if there is no NUMA constraint for the
936 * The pointer to the new allocated mempool, on success. NULL on error
937 * with rte_errno set appropriately. Possible rte_errno values include:
938 * - E_RTE_NO_CONFIG - function could not get pointer to rte_config structure
939 * - E_RTE_SECONDARY - function was called from a secondary process instance
940 * - EINVAL - cache size provided is too large, or priv_size is not aligned.
941 * - ENOSPC - the maximum number of memzones has already been allocated
942 * - EEXIST - a memzone with the same name already exists
943 * - ENOMEM - no appropriate memory area found in which to create memzone
946 rte_pktmbuf_pool_create(const char *name, unsigned n,
947 unsigned cache_size, uint16_t priv_size, uint16_t data_room_size,
951 * Get the data room size of mbufs stored in a pktmbuf_pool
953 * The data room size is the amount of data that can be stored in a
954 * mbuf including the headroom (RTE_PKTMBUF_HEADROOM).
957 * The packet mbuf pool.
959 * The data room size of mbufs stored in this mempool.
961 static inline uint16_t
962 rte_pktmbuf_data_room_size(struct rte_mempool *mp)
964 struct rte_pktmbuf_pool_private *mbp_priv;
966 mbp_priv = (struct rte_pktmbuf_pool_private *)rte_mempool_get_priv(mp);
967 return mbp_priv->mbuf_data_room_size;
971 * Get the application private size of mbufs stored in a pktmbuf_pool
973 * The private size of mbuf is a zone located between the rte_mbuf
974 * structure and the data buffer where an application can store data
975 * associated to a packet.
978 * The packet mbuf pool.
980 * The private size of mbufs stored in this mempool.
982 static inline uint16_t
983 rte_pktmbuf_priv_size(struct rte_mempool *mp)
985 struct rte_pktmbuf_pool_private *mbp_priv;
987 mbp_priv = (struct rte_pktmbuf_pool_private *)rte_mempool_get_priv(mp);
988 return mbp_priv->mbuf_priv_size;
992 * Reset the data_off field of a packet mbuf to its default value.
994 * The given mbuf must have only one segment, which should be empty.
997 * The packet mbuf's data_off field has to be reset.
999 static inline void rte_pktmbuf_reset_headroom(struct rte_mbuf *m)
1001 m->data_off = RTE_MIN(RTE_PKTMBUF_HEADROOM, (uint16_t)m->buf_len);
1005 * Reset the fields of a packet mbuf to their default values.
1007 * The given mbuf must have only one segment.
1010 * The packet mbuf to be resetted.
1012 static inline void rte_pktmbuf_reset(struct rte_mbuf *m)
1018 m->vlan_tci_outer = 0;
1024 rte_pktmbuf_reset_headroom(m);
1027 __rte_mbuf_sanity_check(m, 1);
1031 * Allocate a new mbuf from a mempool.
1033 * This new mbuf contains one segment, which has a length of 0. The pointer
1034 * to data is initialized to have some bytes of headroom in the buffer
1035 * (if buffer size allows).
1038 * The mempool from which the mbuf is allocated.
1040 * - The pointer to the new mbuf on success.
1041 * - NULL if allocation failed.
1043 static inline struct rte_mbuf *rte_pktmbuf_alloc(struct rte_mempool *mp)
1046 if ((m = rte_mbuf_raw_alloc(mp)) != NULL)
1047 rte_pktmbuf_reset(m);
1052 * Allocate a bulk of mbufs, initialize refcnt and reset the fields to default
1056 * The mempool from which mbufs are allocated.
1058 * Array of pointers to mbufs
1064 static inline int rte_pktmbuf_alloc_bulk(struct rte_mempool *pool,
1065 struct rte_mbuf **mbufs, unsigned count)
1070 rc = rte_mempool_get_bulk(pool, (void **)mbufs, count);
1074 /* To understand duff's device on loop unwinding optimization, see
1075 * https://en.wikipedia.org/wiki/Duff's_device.
1076 * Here while() loop is used rather than do() while{} to avoid extra
1077 * check if count is zero.
1079 switch (count % 4) {
1081 while (idx != count) {
1082 RTE_ASSERT(rte_mbuf_refcnt_read(mbufs[idx]) == 0);
1083 rte_mbuf_refcnt_set(mbufs[idx], 1);
1084 rte_pktmbuf_reset(mbufs[idx]);
1087 RTE_ASSERT(rte_mbuf_refcnt_read(mbufs[idx]) == 0);
1088 rte_mbuf_refcnt_set(mbufs[idx], 1);
1089 rte_pktmbuf_reset(mbufs[idx]);
1092 RTE_ASSERT(rte_mbuf_refcnt_read(mbufs[idx]) == 0);
1093 rte_mbuf_refcnt_set(mbufs[idx], 1);
1094 rte_pktmbuf_reset(mbufs[idx]);
1097 RTE_ASSERT(rte_mbuf_refcnt_read(mbufs[idx]) == 0);
1098 rte_mbuf_refcnt_set(mbufs[idx], 1);
1099 rte_pktmbuf_reset(mbufs[idx]);
1107 * Attach packet mbuf to another packet mbuf.
1109 * After attachment we refer the mbuf we attached as 'indirect',
1110 * while mbuf we attached to as 'direct'.
1111 * The direct mbuf's reference counter is incremented.
1113 * Right now, not supported:
1114 * - attachment for already indirect mbuf (e.g. - mi has to be direct).
1115 * - mbuf we trying to attach (mi) is used by someone else
1116 * e.g. it's reference counter is greater then 1.
1119 * The indirect packet mbuf.
1121 * The packet mbuf we're attaching to.
1123 static inline void rte_pktmbuf_attach(struct rte_mbuf *mi, struct rte_mbuf *m)
1125 struct rte_mbuf *md;
1127 RTE_ASSERT(RTE_MBUF_DIRECT(mi) &&
1128 rte_mbuf_refcnt_read(mi) == 1);
1130 /* if m is not direct, get the mbuf that embeds the data */
1131 if (RTE_MBUF_DIRECT(m))
1134 md = rte_mbuf_from_indirect(m);
1136 rte_mbuf_refcnt_update(md, 1);
1137 mi->priv_size = m->priv_size;
1138 mi->buf_physaddr = m->buf_physaddr;
1139 mi->buf_addr = m->buf_addr;
1140 mi->buf_len = m->buf_len;
1143 mi->data_off = m->data_off;
1144 mi->data_len = m->data_len;
1146 mi->vlan_tci = m->vlan_tci;
1147 mi->vlan_tci_outer = m->vlan_tci_outer;
1148 mi->tx_offload = m->tx_offload;
1152 mi->pkt_len = mi->data_len;
1154 mi->ol_flags = m->ol_flags | IND_ATTACHED_MBUF;
1155 mi->packet_type = m->packet_type;
1157 __rte_mbuf_sanity_check(mi, 1);
1158 __rte_mbuf_sanity_check(m, 0);
1162 * Detach an indirect packet mbuf.
1164 * - restore original mbuf address and length values.
1165 * - reset pktmbuf data and data_len to their default values.
1166 * - decrement the direct mbuf's reference counter. When the
1167 * reference counter becomes 0, the direct mbuf is freed.
1169 * All other fields of the given packet mbuf will be left intact.
1172 * The indirect attached packet mbuf.
1174 static inline void rte_pktmbuf_detach(struct rte_mbuf *m)
1176 struct rte_mbuf *md = rte_mbuf_from_indirect(m);
1177 struct rte_mempool *mp = m->pool;
1178 uint32_t mbuf_size, buf_len, priv_size;
1180 priv_size = rte_pktmbuf_priv_size(mp);
1181 mbuf_size = sizeof(struct rte_mbuf) + priv_size;
1182 buf_len = rte_pktmbuf_data_room_size(mp);
1184 m->priv_size = priv_size;
1185 m->buf_addr = (char *)m + mbuf_size;
1186 m->buf_physaddr = rte_mempool_virt2phy(mp, m) + mbuf_size;
1187 m->buf_len = (uint16_t)buf_len;
1188 rte_pktmbuf_reset_headroom(m);
1192 if (rte_mbuf_refcnt_update(md, -1) == 0)
1193 __rte_mbuf_raw_free(md);
1196 static inline struct rte_mbuf* __attribute__((always_inline))
1197 __rte_pktmbuf_prefree_seg(struct rte_mbuf *m)
1199 __rte_mbuf_sanity_check(m, 0);
1201 if (likely(rte_mbuf_refcnt_update(m, -1) == 0)) {
1202 /* if this is an indirect mbuf, it is detached. */
1203 if (RTE_MBUF_INDIRECT(m))
1204 rte_pktmbuf_detach(m);
1211 * Free a segment of a packet mbuf into its original mempool.
1213 * Free an mbuf, without parsing other segments in case of chained
1217 * The packet mbuf segment to be freed.
1219 static inline void __attribute__((always_inline))
1220 rte_pktmbuf_free_seg(struct rte_mbuf *m)
1222 if (likely(NULL != (m = __rte_pktmbuf_prefree_seg(m)))) {
1224 __rte_mbuf_raw_free(m);
1229 * Free a packet mbuf back into its original mempool.
1231 * Free an mbuf, and all its segments in case of chained buffers. Each
1232 * segment is added back into its original mempool.
1235 * The packet mbuf to be freed.
1237 static inline void rte_pktmbuf_free(struct rte_mbuf *m)
1239 struct rte_mbuf *m_next;
1241 __rte_mbuf_sanity_check(m, 1);
1245 rte_pktmbuf_free_seg(m);
1251 * Creates a "clone" of the given packet mbuf.
1253 * Walks through all segments of the given packet mbuf, and for each of them:
1254 * - Creates a new packet mbuf from the given pool.
1255 * - Attaches newly created mbuf to the segment.
1256 * Then updates pkt_len and nb_segs of the "clone" packet mbuf to match values
1257 * from the original packet mbuf.
1260 * The packet mbuf to be cloned.
1262 * The mempool from which the "clone" mbufs are allocated.
1264 * - The pointer to the new "clone" mbuf on success.
1265 * - NULL if allocation fails.
1267 static inline struct rte_mbuf *rte_pktmbuf_clone(struct rte_mbuf *md,
1268 struct rte_mempool *mp)
1270 struct rte_mbuf *mc, *mi, **prev;
1274 if (unlikely ((mc = rte_pktmbuf_alloc(mp)) == NULL))
1279 pktlen = md->pkt_len;
1284 rte_pktmbuf_attach(mi, md);
1287 } while ((md = md->next) != NULL &&
1288 (mi = rte_pktmbuf_alloc(mp)) != NULL);
1292 mc->pkt_len = pktlen;
1294 /* Allocation of new indirect segment failed */
1295 if (unlikely (mi == NULL)) {
1296 rte_pktmbuf_free(mc);
1300 __rte_mbuf_sanity_check(mc, 1);
1305 * Adds given value to the refcnt of all packet mbuf segments.
1307 * Walks through all segments of given packet mbuf and for each of them
1308 * invokes rte_mbuf_refcnt_update().
1311 * The packet mbuf whose refcnt to be updated.
1313 * The value to add to the mbuf's segments refcnt.
1315 static inline void rte_pktmbuf_refcnt_update(struct rte_mbuf *m, int16_t v)
1317 __rte_mbuf_sanity_check(m, 1);
1320 rte_mbuf_refcnt_update(m, v);
1321 } while ((m = m->next) != NULL);
1325 * Get the headroom in a packet mbuf.
1330 * The length of the headroom.
1332 static inline uint16_t rte_pktmbuf_headroom(const struct rte_mbuf *m)
1334 __rte_mbuf_sanity_check(m, 1);
1339 * Get the tailroom of a packet mbuf.
1344 * The length of the tailroom.
1346 static inline uint16_t rte_pktmbuf_tailroom(const struct rte_mbuf *m)
1348 __rte_mbuf_sanity_check(m, 1);
1349 return (uint16_t)(m->buf_len - rte_pktmbuf_headroom(m) -
1354 * Get the last segment of the packet.
1359 * The last segment of the given mbuf.
1361 static inline struct rte_mbuf *rte_pktmbuf_lastseg(struct rte_mbuf *m)
1363 struct rte_mbuf *m2 = (struct rte_mbuf *)m;
1365 __rte_mbuf_sanity_check(m, 1);
1366 while (m2->next != NULL)
1372 * A macro that points to an offset into the data in the mbuf.
1374 * The returned pointer is cast to type t. Before using this
1375 * function, the user must ensure that the first segment is large
1376 * enough to accommodate its data.
1381 * The offset into the mbuf data.
1383 * The type to cast the result into.
1385 #define rte_pktmbuf_mtod_offset(m, t, o) \
1386 ((t)((char *)(m)->buf_addr + (m)->data_off + (o)))
1389 * A macro that points to the start of the data in the mbuf.
1391 * The returned pointer is cast to type t. Before using this
1392 * function, the user must ensure that the first segment is large
1393 * enough to accommodate its data.
1398 * The type to cast the result into.
1400 #define rte_pktmbuf_mtod(m, t) rte_pktmbuf_mtod_offset(m, t, 0)
1403 * A macro that returns the physical address that points to an offset of the
1404 * start of the data in the mbuf
1409 * The offset into the data to calculate address from.
1411 #define rte_pktmbuf_mtophys_offset(m, o) \
1412 (phys_addr_t)((m)->buf_physaddr + (m)->data_off + (o))
1415 * A macro that returns the physical address that points to the start of the
1421 #define rte_pktmbuf_mtophys(m) rte_pktmbuf_mtophys_offset(m, 0)
1424 * A macro that returns the length of the packet.
1426 * The value can be read or assigned.
1431 #define rte_pktmbuf_pkt_len(m) ((m)->pkt_len)
1434 * A macro that returns the length of the segment.
1436 * The value can be read or assigned.
1441 #define rte_pktmbuf_data_len(m) ((m)->data_len)
1444 * Prepend len bytes to an mbuf data area.
1446 * Returns a pointer to the new
1447 * data start address. If there is not enough headroom in the first
1448 * segment, the function will return NULL, without modifying the mbuf.
1453 * The amount of data to prepend (in bytes).
1455 * A pointer to the start of the newly prepended data, or
1456 * NULL if there is not enough headroom space in the first segment
1458 static inline char *rte_pktmbuf_prepend(struct rte_mbuf *m,
1461 __rte_mbuf_sanity_check(m, 1);
1463 if (unlikely(len > rte_pktmbuf_headroom(m)))
1467 m->data_len = (uint16_t)(m->data_len + len);
1468 m->pkt_len = (m->pkt_len + len);
1470 return (char *)m->buf_addr + m->data_off;
1474 * Append len bytes to an mbuf.
1476 * Append len bytes to an mbuf and return a pointer to the start address
1477 * of the added data. If there is not enough tailroom in the last
1478 * segment, the function will return NULL, without modifying the mbuf.
1483 * The amount of data to append (in bytes).
1485 * A pointer to the start of the newly appended data, or
1486 * NULL if there is not enough tailroom space in the last segment
1488 static inline char *rte_pktmbuf_append(struct rte_mbuf *m, uint16_t len)
1491 struct rte_mbuf *m_last;
1493 __rte_mbuf_sanity_check(m, 1);
1495 m_last = rte_pktmbuf_lastseg(m);
1496 if (unlikely(len > rte_pktmbuf_tailroom(m_last)))
1499 tail = (char *)m_last->buf_addr + m_last->data_off + m_last->data_len;
1500 m_last->data_len = (uint16_t)(m_last->data_len + len);
1501 m->pkt_len = (m->pkt_len + len);
1502 return (char*) tail;
1506 * Remove len bytes at the beginning of an mbuf.
1508 * Returns a pointer to the start address of the new data area. If the
1509 * length is greater than the length of the first segment, then the
1510 * function will fail and return NULL, without modifying the mbuf.
1515 * The amount of data to remove (in bytes).
1517 * A pointer to the new start of the data.
1519 static inline char *rte_pktmbuf_adj(struct rte_mbuf *m, uint16_t len)
1521 __rte_mbuf_sanity_check(m, 1);
1523 if (unlikely(len > m->data_len))
1526 m->data_len = (uint16_t)(m->data_len - len);
1528 m->pkt_len = (m->pkt_len - len);
1529 return (char *)m->buf_addr + m->data_off;
1533 * Remove len bytes of data at the end of the mbuf.
1535 * If the length is greater than the length of the last segment, the
1536 * function will fail and return -1 without modifying the mbuf.
1541 * The amount of data to remove (in bytes).
1546 static inline int rte_pktmbuf_trim(struct rte_mbuf *m, uint16_t len)
1548 struct rte_mbuf *m_last;
1550 __rte_mbuf_sanity_check(m, 1);
1552 m_last = rte_pktmbuf_lastseg(m);
1553 if (unlikely(len > m_last->data_len))
1556 m_last->data_len = (uint16_t)(m_last->data_len - len);
1557 m->pkt_len = (m->pkt_len - len);
1562 * Test if mbuf data is contiguous.
1567 * - 1, if all data is contiguous (one segment).
1568 * - 0, if there is several segments.
1570 static inline int rte_pktmbuf_is_contiguous(const struct rte_mbuf *m)
1572 __rte_mbuf_sanity_check(m, 1);
1573 return !!(m->nb_segs == 1);
1577 * @internal used by rte_pktmbuf_read().
1579 const void *__rte_pktmbuf_read(const struct rte_mbuf *m, uint32_t off,
1580 uint32_t len, void *buf);
1583 * Read len data bytes in a mbuf at specified offset.
1585 * If the data is contiguous, return the pointer in the mbuf data, else
1586 * copy the data in the buffer provided by the user and return its
1590 * The pointer to the mbuf.
1592 * The offset of the data in the mbuf.
1594 * The amount of bytes to read.
1596 * The buffer where data is copied if it is not contigous in mbuf
1597 * data. Its length should be at least equal to the len parameter.
1599 * The pointer to the data, either in the mbuf if it is contiguous,
1600 * or in the user buffer. If mbuf is too small, NULL is returned.
1602 static inline const void *rte_pktmbuf_read(const struct rte_mbuf *m,
1603 uint32_t off, uint32_t len, void *buf)
1605 if (likely(off + len <= rte_pktmbuf_data_len(m)))
1606 return rte_pktmbuf_mtod_offset(m, char *, off);
1608 return __rte_pktmbuf_read(m, off, len, buf);
1612 * Chain an mbuf to another, thereby creating a segmented packet.
1614 * Note: The implementation will do a linear walk over the segments to find
1615 * the tail entry. For cases when there are many segments, it's better to
1616 * chain the entries manually.
1619 * The head of the mbuf chain (the first packet)
1621 * The mbuf to put last in the chain
1625 * - -EOVERFLOW, if the chain is full (256 entries)
1627 static inline int rte_pktmbuf_chain(struct rte_mbuf *head, struct rte_mbuf *tail)
1629 struct rte_mbuf *cur_tail;
1631 /* Check for number-of-segments-overflow */
1632 if (head->nb_segs + tail->nb_segs >= 1 << (sizeof(head->nb_segs) * 8))
1635 /* Chain 'tail' onto the old tail */
1636 cur_tail = rte_pktmbuf_lastseg(head);
1637 cur_tail->next = tail;
1639 /* accumulate number of segments and total length. */
1640 head->nb_segs = (uint8_t)(head->nb_segs + tail->nb_segs);
1641 head->pkt_len += tail->pkt_len;
1643 /* pkt_len is only set in the head */
1644 tail->pkt_len = tail->data_len;
1650 * Dump an mbuf structure to a file.
1652 * Dump all fields for the given packet mbuf and all its associated
1653 * segments (in the case of a chained buffer).
1656 * A pointer to a file for output
1660 * If dump_len != 0, also dump the "dump_len" first data bytes of
1663 void rte_pktmbuf_dump(FILE *f, const struct rte_mbuf *m, unsigned dump_len);
1669 #endif /* _RTE_MBUF_H_ */