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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 provides 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
208 * - fill the mbuf offload information: l2_len, l3_len, l4_len, tso_segsz
210 #define PKT_TX_TCP_SEG (1ULL << 50)
212 #define PKT_TX_IEEE1588_TMST (1ULL << 51) /**< TX IEEE1588 packet to timestamp. */
215 * Bits 52+53 used for L4 packet type with checksum enabled: 00: Reserved,
216 * 01: TCP checksum, 10: SCTP checksum, 11: UDP checksum. To use hardware
217 * L4 checksum offload, the user needs to:
218 * - fill l2_len and l3_len in mbuf
219 * - set the flags PKT_TX_TCP_CKSUM, PKT_TX_SCTP_CKSUM or PKT_TX_UDP_CKSUM
220 * - set the flag PKT_TX_IPV4 or PKT_TX_IPV6
222 #define PKT_TX_L4_NO_CKSUM (0ULL << 52) /**< Disable L4 cksum of TX pkt. */
223 #define PKT_TX_TCP_CKSUM (1ULL << 52) /**< TCP cksum of TX pkt. computed by NIC. */
224 #define PKT_TX_SCTP_CKSUM (2ULL << 52) /**< SCTP cksum of TX pkt. computed by NIC. */
225 #define PKT_TX_UDP_CKSUM (3ULL << 52) /**< UDP cksum of TX pkt. computed by NIC. */
226 #define PKT_TX_L4_MASK (3ULL << 52) /**< Mask for L4 cksum offload request. */
229 * Offload the IP checksum in the hardware. The flag PKT_TX_IPV4 should
230 * also be set by the application, although a PMD will only check
232 * - fill the mbuf offload information: l2_len, l3_len
234 #define PKT_TX_IP_CKSUM (1ULL << 54)
237 * Packet is IPv4. This flag must be set when using any offload feature
238 * (TSO, L3 or L4 checksum) to tell the NIC that the packet is an IPv4
239 * packet. If the packet is a tunneled packet, this flag is related to
242 #define PKT_TX_IPV4 (1ULL << 55)
245 * Packet is IPv6. This flag must be set when using an offload feature
246 * (TSO or L4 checksum) to tell the NIC that the packet is an IPv6
247 * packet. If the packet is a tunneled packet, this flag is related to
250 #define PKT_TX_IPV6 (1ULL << 56)
252 #define PKT_TX_VLAN_PKT (1ULL << 57) /**< TX packet is a 802.1q VLAN packet. */
255 * Offload the IP checksum of an external header in the hardware. The
256 * flag PKT_TX_OUTER_IPV4 should also be set by the application, although
257 * a PMD will only check PKT_TX_OUTER_IP_CKSUM.
258 * - fill the mbuf offload information: outer_l2_len, outer_l3_len
260 #define PKT_TX_OUTER_IP_CKSUM (1ULL << 58)
263 * Packet outer header is IPv4. This flag must be set when using any
264 * outer offload feature (L3 or L4 checksum) to tell the NIC that the
265 * outer header of the tunneled packet is an IPv4 packet.
267 #define PKT_TX_OUTER_IPV4 (1ULL << 59)
270 * Packet outer header is IPv6. This flag must be set when using any
271 * outer offload feature (L4 checksum) to tell the NIC that the outer
272 * header of the tunneled packet is an IPv6 packet.
274 #define PKT_TX_OUTER_IPV6 (1ULL << 60)
276 #define __RESERVED (1ULL << 61) /**< reserved for future mbuf use */
278 #define IND_ATTACHED_MBUF (1ULL << 62) /**< Indirect attached mbuf */
280 /* Use final bit of flags to indicate a control mbuf */
281 #define CTRL_MBUF_FLAG (1ULL << 63) /**< Mbuf contains control data */
283 /** Alignment constraint of mbuf private area. */
284 #define RTE_MBUF_PRIV_ALIGN 8
287 * Get the name of a RX offload flag
290 * The mask describing the flag.
292 * The name of this flag, or NULL if it's not a valid RX flag.
294 const char *rte_get_rx_ol_flag_name(uint64_t mask);
297 * Dump the list of RX offload flags in a buffer
300 * The mask describing the RX flags.
304 * The length of the buffer.
306 * 0 on success, (-1) on error.
308 int rte_get_rx_ol_flag_list(uint64_t mask, char *buf, size_t buflen);
311 * Get the name of a TX offload flag
314 * The mask describing the flag. Usually only one bit must be set.
315 * Several bits can be given if they belong to the same mask.
316 * Ex: PKT_TX_L4_MASK.
318 * The name of this flag, or NULL if it's not a valid TX flag.
320 const char *rte_get_tx_ol_flag_name(uint64_t mask);
323 * Dump the list of TX offload flags in a buffer
326 * The mask describing the TX flags.
330 * The length of the buffer.
332 * 0 on success, (-1) on error.
334 int rte_get_tx_ol_flag_list(uint64_t mask, char *buf, size_t buflen);
337 * Some NICs need at least 2KB buffer to RX standard Ethernet frame without
338 * splitting it into multiple segments.
339 * So, for mbufs that planned to be involved into RX/TX, the recommended
340 * minimal buffer length is 2KB + RTE_PKTMBUF_HEADROOM.
342 #define RTE_MBUF_DEFAULT_DATAROOM 2048
343 #define RTE_MBUF_DEFAULT_BUF_SIZE \
344 (RTE_MBUF_DEFAULT_DATAROOM + RTE_PKTMBUF_HEADROOM)
346 /* define a set of marker types that can be used to refer to set points in the
349 typedef void *MARKER[0]; /**< generic marker for a point in a structure */
351 typedef uint8_t MARKER8[0]; /**< generic marker with 1B alignment */
353 typedef uint64_t MARKER64[0]; /**< marker that allows us to overwrite 8 bytes
354 * with a single assignment */
357 * The generic rte_mbuf, containing a packet mbuf.
362 void *buf_addr; /**< Virtual address of segment buffer. */
363 phys_addr_t buf_physaddr; /**< Physical address of segment buffer. */
365 uint16_t buf_len; /**< Length of segment buffer. */
367 /* next 6 bytes are initialised on RX descriptor rearm */
372 * 16-bit Reference counter.
373 * It should only be accessed using the following functions:
374 * rte_mbuf_refcnt_update(), rte_mbuf_refcnt_read(), and
375 * rte_mbuf_refcnt_set(). The functionality of these functions (atomic,
376 * or non-atomic) is controlled by the CONFIG_RTE_MBUF_REFCNT_ATOMIC
381 rte_atomic16_t refcnt_atomic; /**< Atomically accessed refcnt */
382 uint16_t refcnt; /**< Non-atomically accessed refcnt */
384 uint8_t nb_segs; /**< Number of segments. */
385 uint8_t port; /**< Input port. */
387 uint64_t ol_flags; /**< Offload features. */
389 /* remaining bytes are set on RX when pulling packet from descriptor */
390 MARKER rx_descriptor_fields1;
393 * The packet type, which is the combination of outer/inner L2, L3, L4
394 * and tunnel types. The packet_type is about data really present in the
395 * mbuf. Example: if vlan stripping is enabled, a received vlan packet
396 * would have RTE_PTYPE_L2_ETHER and not RTE_PTYPE_L2_VLAN because the
397 * vlan is stripped from the data.
401 uint32_t packet_type; /**< L2/L3/L4 and tunnel information. */
403 uint32_t l2_type:4; /**< (Outer) L2 type. */
404 uint32_t l3_type:4; /**< (Outer) L3 type. */
405 uint32_t l4_type:4; /**< (Outer) L4 type. */
406 uint32_t tun_type:4; /**< Tunnel type. */
407 uint32_t inner_l2_type:4; /**< Inner L2 type. */
408 uint32_t inner_l3_type:4; /**< Inner L3 type. */
409 uint32_t inner_l4_type:4; /**< Inner L4 type. */
413 uint32_t pkt_len; /**< Total pkt len: sum of all segments. */
414 uint16_t data_len; /**< Amount of data in segment buffer. */
415 /** VLAN TCI (CPU order), valid if PKT_RX_VLAN_STRIPPED is set. */
419 uint32_t rss; /**< RSS hash result if RSS enabled */
428 /**< Second 4 flexible bytes */
431 /**< First 4 flexible bytes or FD ID, dependent on
432 PKT_RX_FDIR_* flag in ol_flags. */
433 } fdir; /**< Filter identifier if FDIR enabled */
437 } sched; /**< Hierarchical scheduler */
438 uint32_t usr; /**< User defined tags. See rte_distributor_process() */
439 } hash; /**< hash information */
441 uint32_t seqn; /**< Sequence number. See also rte_reorder_insert() */
443 /** Outer VLAN TCI (CPU order), valid if PKT_RX_QINQ_STRIPPED is set. */
444 uint16_t vlan_tci_outer;
446 /* second cache line - fields only used in slow path or on TX */
447 MARKER cacheline1 __rte_cache_min_aligned;
451 void *userdata; /**< Can be used for external metadata */
452 uint64_t udata64; /**< Allow 8-byte userdata on 32-bit */
455 struct rte_mempool *pool; /**< Pool from which mbuf was allocated. */
456 struct rte_mbuf *next; /**< Next segment of scattered packet. */
458 /* fields to support TX offloads */
461 uint64_t tx_offload; /**< combined for easy fetch */
465 /**< L2 (MAC) Header Length for non-tunneling pkt.
466 * Outer_L4_len + ... + Inner_L2_len for tunneling pkt.
468 uint64_t l3_len:9; /**< L3 (IP) Header Length. */
469 uint64_t l4_len:8; /**< L4 (TCP/UDP) Header Length. */
470 uint64_t tso_segsz:16; /**< TCP TSO segment size */
472 /* fields for TX offloading of tunnels */
473 uint64_t outer_l3_len:9; /**< Outer L3 (IP) Hdr Length. */
474 uint64_t outer_l2_len:7; /**< Outer L2 (MAC) Hdr Length. */
476 /* uint64_t unused:8; */
480 /** Size of the application private data. In case of an indirect
481 * mbuf, it stores the direct mbuf private data size. */
484 /** Timesync flags for use with IEEE1588. */
486 } __rte_cache_aligned;
489 * Prefetch the first part of the mbuf
491 * The first 64 bytes of the mbuf corresponds to fields that are used early
492 * in the receive path. If the cache line of the architecture is higher than
493 * 64B, the second part will also be prefetched.
496 * The pointer to the mbuf.
499 rte_mbuf_prefetch_part1(struct rte_mbuf *m)
501 rte_prefetch0(&m->cacheline0);
505 * Prefetch the second part of the mbuf
507 * The next 64 bytes of the mbuf corresponds to fields that are used in the
508 * transmit path. If the cache line of the architecture is higher than 64B,
509 * this function does nothing as it is expected that the full mbuf is
513 * The pointer to the mbuf.
516 rte_mbuf_prefetch_part2(struct rte_mbuf *m)
518 #if RTE_CACHE_LINE_SIZE == 64
519 rte_prefetch0(&m->cacheline1);
526 static inline uint16_t rte_pktmbuf_priv_size(struct rte_mempool *mp);
529 * Return the DMA address of the beginning of the mbuf data
532 * The pointer to the mbuf.
534 * The physical address of the beginning of the mbuf data
536 static inline phys_addr_t
537 rte_mbuf_data_dma_addr(const struct rte_mbuf *mb)
539 return mb->buf_physaddr + mb->data_off;
543 * Return the default DMA address of the beginning of the mbuf data
545 * This function is used by drivers in their receive function, as it
546 * returns the location where data should be written by the NIC, taking
547 * the default headroom in account.
550 * The pointer to the mbuf.
552 * The physical address of the beginning of the mbuf data
554 static inline phys_addr_t
555 rte_mbuf_data_dma_addr_default(const struct rte_mbuf *mb)
557 return mb->buf_physaddr + RTE_PKTMBUF_HEADROOM;
561 * Return the mbuf owning the data buffer address of an indirect mbuf.
564 * The pointer to the indirect mbuf.
566 * The address of the direct mbuf corresponding to buffer_addr.
568 static inline struct rte_mbuf *
569 rte_mbuf_from_indirect(struct rte_mbuf *mi)
571 return (struct rte_mbuf *)RTE_PTR_SUB(mi->buf_addr, sizeof(*mi) + mi->priv_size);
575 * Return the buffer address embedded in the given mbuf.
578 * The pointer to the mbuf.
580 * The address of the data buffer owned by the mbuf.
583 rte_mbuf_to_baddr(struct rte_mbuf *md)
586 buffer_addr = (char *)md + sizeof(*md) + rte_pktmbuf_priv_size(md->pool);
591 * Returns TRUE if given mbuf is indirect, or FALSE otherwise.
593 #define RTE_MBUF_INDIRECT(mb) ((mb)->ol_flags & IND_ATTACHED_MBUF)
596 * Returns TRUE if given mbuf is direct, or FALSE otherwise.
598 #define RTE_MBUF_DIRECT(mb) (!RTE_MBUF_INDIRECT(mb))
601 * Private data in case of pktmbuf pool.
603 * A structure that contains some pktmbuf_pool-specific data that are
604 * appended after the mempool structure (in private data).
606 struct rte_pktmbuf_pool_private {
607 uint16_t mbuf_data_room_size; /**< Size of data space in each mbuf. */
608 uint16_t mbuf_priv_size; /**< Size of private area in each mbuf. */
611 #ifdef RTE_LIBRTE_MBUF_DEBUG
613 /** check mbuf type in debug mode */
614 #define __rte_mbuf_sanity_check(m, is_h) rte_mbuf_sanity_check(m, is_h)
616 #else /* RTE_LIBRTE_MBUF_DEBUG */
618 /** check mbuf type in debug mode */
619 #define __rte_mbuf_sanity_check(m, is_h) do { } while (0)
621 #endif /* RTE_LIBRTE_MBUF_DEBUG */
623 #ifdef RTE_MBUF_REFCNT_ATOMIC
626 * Reads the value of an mbuf's refcnt.
630 * Reference count number.
632 static inline uint16_t
633 rte_mbuf_refcnt_read(const struct rte_mbuf *m)
635 return (uint16_t)(rte_atomic16_read(&m->refcnt_atomic));
639 * Sets an mbuf's refcnt to a defined value.
646 rte_mbuf_refcnt_set(struct rte_mbuf *m, uint16_t new_value)
648 rte_atomic16_set(&m->refcnt_atomic, (int16_t)new_value);
652 * Adds given value to an mbuf's refcnt and returns its new value.
656 * Value to add/subtract
660 static inline uint16_t
661 rte_mbuf_refcnt_update(struct rte_mbuf *m, int16_t value)
664 * The atomic_add is an expensive operation, so we don't want to
665 * call it in the case where we know we are the uniq holder of
666 * this mbuf (i.e. ref_cnt == 1). Otherwise, an atomic
667 * operation has to be used because concurrent accesses on the
668 * reference counter can occur.
670 if (likely(rte_mbuf_refcnt_read(m) == 1)) {
672 rte_mbuf_refcnt_set(m, (uint16_t)value);
673 return (uint16_t)value;
676 return (uint16_t)(rte_atomic16_add_return(&m->refcnt_atomic, value));
679 #else /* ! RTE_MBUF_REFCNT_ATOMIC */
682 * Adds given value to an mbuf's refcnt and returns its new value.
684 static inline uint16_t
685 rte_mbuf_refcnt_update(struct rte_mbuf *m, int16_t value)
687 m->refcnt = (uint16_t)(m->refcnt + value);
692 * Reads the value of an mbuf's refcnt.
694 static inline uint16_t
695 rte_mbuf_refcnt_read(const struct rte_mbuf *m)
701 * Sets an mbuf's refcnt to the defined value.
704 rte_mbuf_refcnt_set(struct rte_mbuf *m, uint16_t new_value)
706 m->refcnt = new_value;
709 #endif /* RTE_MBUF_REFCNT_ATOMIC */
712 #define RTE_MBUF_PREFETCH_TO_FREE(m) do { \
719 * Sanity checks on an mbuf.
721 * Check the consistency of the given mbuf. The function will cause a
722 * panic if corruption is detected.
725 * The mbuf to be checked.
727 * True if the mbuf is a packet header, false if it is a sub-segment
728 * of a packet (in this case, some fields like nb_segs are not checked)
731 rte_mbuf_sanity_check(const struct rte_mbuf *m, int is_header);
734 * Allocate an unitialized mbuf from mempool *mp*.
736 * This function can be used by PMDs (especially in RX functions) to
737 * allocate an unitialized mbuf. The driver is responsible of
738 * initializing all the required fields. See rte_pktmbuf_reset().
739 * For standard needs, prefer rte_pktmbuf_alloc().
742 * The mempool from which mbuf is allocated.
744 * - The pointer to the new mbuf on success.
745 * - NULL if allocation failed.
747 static inline struct rte_mbuf *rte_mbuf_raw_alloc(struct rte_mempool *mp)
752 if (rte_mempool_get(mp, &mb) < 0)
754 m = (struct rte_mbuf *)mb;
755 RTE_ASSERT(rte_mbuf_refcnt_read(m) == 0);
756 rte_mbuf_refcnt_set(m, 1);
757 __rte_mbuf_sanity_check(m, 0);
763 * @internal Put mbuf back into its original mempool.
764 * The use of that function is reserved for RTE internal needs.
765 * Please use rte_pktmbuf_free().
768 * The mbuf to be freed.
770 static inline void __attribute__((always_inline))
771 __rte_mbuf_raw_free(struct rte_mbuf *m)
773 RTE_ASSERT(rte_mbuf_refcnt_read(m) == 0);
774 rte_mempool_put(m->pool, m);
777 /* Operations on ctrl mbuf */
780 * The control mbuf constructor.
782 * This function initializes some fields in an mbuf structure that are
783 * not modified by the user once created (mbuf type, origin pool, buffer
784 * start address, and so on). This function is given as a callback function
785 * to rte_mempool_create() at pool creation time.
788 * The mempool from which the mbuf is allocated.
790 * A pointer that can be used by the user to retrieve useful information
791 * for mbuf initialization. This pointer comes from the ``init_arg``
792 * parameter of rte_mempool_create().
794 * The mbuf to initialize.
796 * The index of the mbuf in the pool table.
798 void rte_ctrlmbuf_init(struct rte_mempool *mp, void *opaque_arg,
799 void *m, unsigned i);
802 * Allocate a new mbuf (type is ctrl) from mempool *mp*.
804 * This new mbuf is initialized with data pointing to the beginning of
805 * buffer, and with a length of zero.
808 * The mempool from which the mbuf is allocated.
810 * - The pointer to the new mbuf on success.
811 * - NULL if allocation failed.
813 #define rte_ctrlmbuf_alloc(mp) rte_pktmbuf_alloc(mp)
816 * Free a control mbuf back into its original mempool.
819 * The control mbuf to be freed.
821 #define rte_ctrlmbuf_free(m) rte_pktmbuf_free(m)
824 * A macro that returns the pointer to the carried data.
826 * The value that can be read or assigned.
831 #define rte_ctrlmbuf_data(m) ((char *)((m)->buf_addr) + (m)->data_off)
834 * A macro that returns the length of the carried data.
836 * The value that can be read or assigned.
841 #define rte_ctrlmbuf_len(m) rte_pktmbuf_data_len(m)
844 * Tests if an mbuf is a control mbuf
847 * The mbuf to be tested
849 * - True (1) if the mbuf is a control mbuf
850 * - False(0) otherwise
853 rte_is_ctrlmbuf(struct rte_mbuf *m)
855 return !!(m->ol_flags & CTRL_MBUF_FLAG);
858 /* Operations on pkt mbuf */
861 * The packet mbuf constructor.
863 * This function initializes some fields in the mbuf structure that are
864 * not modified by the user once created (origin pool, buffer start
865 * address, and so on). This function is given as a callback function to
866 * rte_mempool_create() at pool creation time.
869 * The mempool from which mbufs originate.
871 * A pointer that can be used by the user to retrieve useful information
872 * for mbuf initialization. This pointer comes from the ``init_arg``
873 * parameter of rte_mempool_create().
875 * The mbuf to initialize.
877 * The index of the mbuf in the pool table.
879 void rte_pktmbuf_init(struct rte_mempool *mp, void *opaque_arg,
880 void *m, unsigned i);
884 * A packet mbuf pool constructor.
886 * This function initializes the mempool private data in the case of a
887 * pktmbuf pool. This private data is needed by the driver. The
888 * function is given as a callback function to rte_mempool_create() at
889 * pool creation. It can be extended by the user, for example, to
890 * provide another packet size.
893 * The mempool from which mbufs originate.
895 * A pointer that can be used by the user to retrieve useful information
896 * for mbuf initialization. This pointer comes from the ``init_arg``
897 * parameter of rte_mempool_create().
899 void rte_pktmbuf_pool_init(struct rte_mempool *mp, void *opaque_arg);
902 * Create a mbuf pool.
904 * This function creates and initializes a packet mbuf pool. It is
905 * a wrapper to rte_mempool_create() with the proper packet constructor
906 * and mempool constructor.
909 * The name of the mbuf pool.
911 * The number of elements in the mbuf pool. The optimum size (in terms
912 * of memory usage) for a mempool is when n is a power of two minus one:
915 * Size of the per-core object cache. See rte_mempool_create() for
918 * Size of application private are between the rte_mbuf structure
919 * and the data buffer. This value must be aligned to RTE_MBUF_PRIV_ALIGN.
920 * @param data_room_size
921 * Size of data buffer in each mbuf, including RTE_PKTMBUF_HEADROOM.
923 * The socket identifier where the memory should be allocated. The
924 * value can be *SOCKET_ID_ANY* if there is no NUMA constraint for the
927 * The pointer to the new allocated mempool, on success. NULL on error
928 * with rte_errno set appropriately. Possible rte_errno values include:
929 * - E_RTE_NO_CONFIG - function could not get pointer to rte_config structure
930 * - E_RTE_SECONDARY - function was called from a secondary process instance
931 * - EINVAL - cache size provided is too large, or priv_size is not aligned.
932 * - ENOSPC - the maximum number of memzones has already been allocated
933 * - EEXIST - a memzone with the same name already exists
934 * - ENOMEM - no appropriate memory area found in which to create memzone
937 rte_pktmbuf_pool_create(const char *name, unsigned n,
938 unsigned cache_size, uint16_t priv_size, uint16_t data_room_size,
942 * Get the data room size of mbufs stored in a pktmbuf_pool
944 * The data room size is the amount of data that can be stored in a
945 * mbuf including the headroom (RTE_PKTMBUF_HEADROOM).
948 * The packet mbuf pool.
950 * The data room size of mbufs stored in this mempool.
952 static inline uint16_t
953 rte_pktmbuf_data_room_size(struct rte_mempool *mp)
955 struct rte_pktmbuf_pool_private *mbp_priv;
957 mbp_priv = (struct rte_pktmbuf_pool_private *)rte_mempool_get_priv(mp);
958 return mbp_priv->mbuf_data_room_size;
962 * Get the application private size of mbufs stored in a pktmbuf_pool
964 * The private size of mbuf is a zone located between the rte_mbuf
965 * structure and the data buffer where an application can store data
966 * associated to a packet.
969 * The packet mbuf pool.
971 * The private size of mbufs stored in this mempool.
973 static inline uint16_t
974 rte_pktmbuf_priv_size(struct rte_mempool *mp)
976 struct rte_pktmbuf_pool_private *mbp_priv;
978 mbp_priv = (struct rte_pktmbuf_pool_private *)rte_mempool_get_priv(mp);
979 return mbp_priv->mbuf_priv_size;
983 * Reset the data_off field of a packet mbuf to its default value.
985 * The given mbuf must have only one segment, which should be empty.
988 * The packet mbuf's data_off field has to be reset.
990 static inline void rte_pktmbuf_reset_headroom(struct rte_mbuf *m)
992 m->data_off = (uint16_t)RTE_MIN((uint16_t)RTE_PKTMBUF_HEADROOM,
993 (uint16_t)m->buf_len);
997 * Reset the fields of a packet mbuf to their default values.
999 * The given mbuf must have only one segment.
1002 * The packet mbuf to be resetted.
1004 static inline void rte_pktmbuf_reset(struct rte_mbuf *m)
1010 m->vlan_tci_outer = 0;
1016 rte_pktmbuf_reset_headroom(m);
1019 __rte_mbuf_sanity_check(m, 1);
1023 * Allocate a new mbuf from a mempool.
1025 * This new mbuf contains one segment, which has a length of 0. The pointer
1026 * to data is initialized to have some bytes of headroom in the buffer
1027 * (if buffer size allows).
1030 * The mempool from which the mbuf is allocated.
1032 * - The pointer to the new mbuf on success.
1033 * - NULL if allocation failed.
1035 static inline struct rte_mbuf *rte_pktmbuf_alloc(struct rte_mempool *mp)
1038 if ((m = rte_mbuf_raw_alloc(mp)) != NULL)
1039 rte_pktmbuf_reset(m);
1044 * Allocate a bulk of mbufs, initialize refcnt and reset the fields to default
1048 * The mempool from which mbufs are allocated.
1050 * Array of pointers to mbufs
1055 * - -ENOENT: Not enough entries in the mempool; no mbufs are retrieved.
1057 static inline int rte_pktmbuf_alloc_bulk(struct rte_mempool *pool,
1058 struct rte_mbuf **mbufs, unsigned count)
1063 rc = rte_mempool_get_bulk(pool, (void **)mbufs, count);
1067 /* To understand duff's device on loop unwinding optimization, see
1068 * https://en.wikipedia.org/wiki/Duff's_device.
1069 * Here while() loop is used rather than do() while{} to avoid extra
1070 * check if count is zero.
1072 switch (count % 4) {
1074 while (idx != count) {
1075 RTE_ASSERT(rte_mbuf_refcnt_read(mbufs[idx]) == 0);
1076 rte_mbuf_refcnt_set(mbufs[idx], 1);
1077 rte_pktmbuf_reset(mbufs[idx]);
1080 RTE_ASSERT(rte_mbuf_refcnt_read(mbufs[idx]) == 0);
1081 rte_mbuf_refcnt_set(mbufs[idx], 1);
1082 rte_pktmbuf_reset(mbufs[idx]);
1085 RTE_ASSERT(rte_mbuf_refcnt_read(mbufs[idx]) == 0);
1086 rte_mbuf_refcnt_set(mbufs[idx], 1);
1087 rte_pktmbuf_reset(mbufs[idx]);
1090 RTE_ASSERT(rte_mbuf_refcnt_read(mbufs[idx]) == 0);
1091 rte_mbuf_refcnt_set(mbufs[idx], 1);
1092 rte_pktmbuf_reset(mbufs[idx]);
1100 * Attach packet mbuf to another packet mbuf.
1102 * After attachment we refer the mbuf we attached as 'indirect',
1103 * while mbuf we attached to as 'direct'.
1104 * The direct mbuf's reference counter is incremented.
1106 * Right now, not supported:
1107 * - attachment for already indirect mbuf (e.g. - mi has to be direct).
1108 * - mbuf we trying to attach (mi) is used by someone else
1109 * e.g. it's reference counter is greater then 1.
1112 * The indirect packet mbuf.
1114 * The packet mbuf we're attaching to.
1116 static inline void rte_pktmbuf_attach(struct rte_mbuf *mi, struct rte_mbuf *m)
1118 struct rte_mbuf *md;
1120 RTE_ASSERT(RTE_MBUF_DIRECT(mi) &&
1121 rte_mbuf_refcnt_read(mi) == 1);
1123 /* if m is not direct, get the mbuf that embeds the data */
1124 if (RTE_MBUF_DIRECT(m))
1127 md = rte_mbuf_from_indirect(m);
1129 rte_mbuf_refcnt_update(md, 1);
1130 mi->priv_size = m->priv_size;
1131 mi->buf_physaddr = m->buf_physaddr;
1132 mi->buf_addr = m->buf_addr;
1133 mi->buf_len = m->buf_len;
1136 mi->data_off = m->data_off;
1137 mi->data_len = m->data_len;
1139 mi->vlan_tci = m->vlan_tci;
1140 mi->vlan_tci_outer = m->vlan_tci_outer;
1141 mi->tx_offload = m->tx_offload;
1145 mi->pkt_len = mi->data_len;
1147 mi->ol_flags = m->ol_flags | IND_ATTACHED_MBUF;
1148 mi->packet_type = m->packet_type;
1150 __rte_mbuf_sanity_check(mi, 1);
1151 __rte_mbuf_sanity_check(m, 0);
1155 * Detach an indirect packet mbuf.
1157 * - restore original mbuf address and length values.
1158 * - reset pktmbuf data and data_len to their default values.
1159 * - decrement the direct mbuf's reference counter. When the
1160 * reference counter becomes 0, the direct mbuf is freed.
1162 * All other fields of the given packet mbuf will be left intact.
1165 * The indirect attached packet mbuf.
1167 static inline void rte_pktmbuf_detach(struct rte_mbuf *m)
1169 struct rte_mbuf *md = rte_mbuf_from_indirect(m);
1170 struct rte_mempool *mp = m->pool;
1171 uint32_t mbuf_size, buf_len;
1174 priv_size = rte_pktmbuf_priv_size(mp);
1175 mbuf_size = (uint32_t)(sizeof(struct rte_mbuf) + priv_size);
1176 buf_len = rte_pktmbuf_data_room_size(mp);
1178 m->priv_size = priv_size;
1179 m->buf_addr = (char *)m + mbuf_size;
1180 m->buf_physaddr = rte_mempool_virt2phy(mp, m) + mbuf_size;
1181 m->buf_len = (uint16_t)buf_len;
1182 rte_pktmbuf_reset_headroom(m);
1186 if (rte_mbuf_refcnt_update(md, -1) == 0)
1187 __rte_mbuf_raw_free(md);
1190 static inline struct rte_mbuf* __attribute__((always_inline))
1191 __rte_pktmbuf_prefree_seg(struct rte_mbuf *m)
1193 __rte_mbuf_sanity_check(m, 0);
1195 if (likely(rte_mbuf_refcnt_update(m, -1) == 0)) {
1196 /* if this is an indirect mbuf, it is detached. */
1197 if (RTE_MBUF_INDIRECT(m))
1198 rte_pktmbuf_detach(m);
1205 * Free a segment of a packet mbuf into its original mempool.
1207 * Free an mbuf, without parsing other segments in case of chained
1211 * The packet mbuf segment to be freed.
1213 static inline void __attribute__((always_inline))
1214 rte_pktmbuf_free_seg(struct rte_mbuf *m)
1216 if (likely(NULL != (m = __rte_pktmbuf_prefree_seg(m)))) {
1218 __rte_mbuf_raw_free(m);
1223 * Free a packet mbuf back into its original mempool.
1225 * Free an mbuf, and all its segments in case of chained buffers. Each
1226 * segment is added back into its original mempool.
1229 * The packet mbuf to be freed. If NULL, the function does nothing.
1231 static inline void rte_pktmbuf_free(struct rte_mbuf *m)
1233 struct rte_mbuf *m_next;
1236 __rte_mbuf_sanity_check(m, 1);
1240 rte_pktmbuf_free_seg(m);
1246 * Creates a "clone" of the given packet mbuf.
1248 * Walks through all segments of the given packet mbuf, and for each of them:
1249 * - Creates a new packet mbuf from the given pool.
1250 * - Attaches newly created mbuf to the segment.
1251 * Then updates pkt_len and nb_segs of the "clone" packet mbuf to match values
1252 * from the original packet mbuf.
1255 * The packet mbuf to be cloned.
1257 * The mempool from which the "clone" mbufs are allocated.
1259 * - The pointer to the new "clone" mbuf on success.
1260 * - NULL if allocation fails.
1262 static inline struct rte_mbuf *rte_pktmbuf_clone(struct rte_mbuf *md,
1263 struct rte_mempool *mp)
1265 struct rte_mbuf *mc, *mi, **prev;
1269 if (unlikely ((mc = rte_pktmbuf_alloc(mp)) == NULL))
1274 pktlen = md->pkt_len;
1279 rte_pktmbuf_attach(mi, md);
1282 } while ((md = md->next) != NULL &&
1283 (mi = rte_pktmbuf_alloc(mp)) != NULL);
1287 mc->pkt_len = pktlen;
1289 /* Allocation of new indirect segment failed */
1290 if (unlikely (mi == NULL)) {
1291 rte_pktmbuf_free(mc);
1295 __rte_mbuf_sanity_check(mc, 1);
1300 * Adds given value to the refcnt of all packet mbuf segments.
1302 * Walks through all segments of given packet mbuf and for each of them
1303 * invokes rte_mbuf_refcnt_update().
1306 * The packet mbuf whose refcnt to be updated.
1308 * The value to add to the mbuf's segments refcnt.
1310 static inline void rte_pktmbuf_refcnt_update(struct rte_mbuf *m, int16_t v)
1312 __rte_mbuf_sanity_check(m, 1);
1315 rte_mbuf_refcnt_update(m, v);
1316 } while ((m = m->next) != NULL);
1320 * Get the headroom in a packet mbuf.
1325 * The length of the headroom.
1327 static inline uint16_t rte_pktmbuf_headroom(const struct rte_mbuf *m)
1329 __rte_mbuf_sanity_check(m, 0);
1334 * Get the tailroom of a packet mbuf.
1339 * The length of the tailroom.
1341 static inline uint16_t rte_pktmbuf_tailroom(const struct rte_mbuf *m)
1343 __rte_mbuf_sanity_check(m, 0);
1344 return (uint16_t)(m->buf_len - rte_pktmbuf_headroom(m) -
1349 * Get the last segment of the packet.
1354 * The last segment of the given mbuf.
1356 static inline struct rte_mbuf *rte_pktmbuf_lastseg(struct rte_mbuf *m)
1358 __rte_mbuf_sanity_check(m, 1);
1359 while (m->next != NULL)
1365 * A macro that points to an offset into the data in the mbuf.
1367 * The returned pointer is cast to type t. Before using this
1368 * function, the user must ensure that the first segment is large
1369 * enough to accommodate its data.
1374 * The offset into the mbuf data.
1376 * The type to cast the result into.
1378 #define rte_pktmbuf_mtod_offset(m, t, o) \
1379 ((t)((char *)(m)->buf_addr + (m)->data_off + (o)))
1382 * A macro that points to the start of the data in the mbuf.
1384 * The returned pointer is cast to type t. Before using this
1385 * function, the user must ensure that the first segment is large
1386 * enough to accommodate its data.
1391 * The type to cast the result into.
1393 #define rte_pktmbuf_mtod(m, t) rte_pktmbuf_mtod_offset(m, t, 0)
1396 * A macro that returns the physical address that points to an offset of the
1397 * start of the data in the mbuf
1402 * The offset into the data to calculate address from.
1404 #define rte_pktmbuf_mtophys_offset(m, o) \
1405 (phys_addr_t)((m)->buf_physaddr + (m)->data_off + (o))
1408 * A macro that returns the physical address that points to the start of the
1414 #define rte_pktmbuf_mtophys(m) rte_pktmbuf_mtophys_offset(m, 0)
1417 * A macro that returns the length of the packet.
1419 * The value can be read or assigned.
1424 #define rte_pktmbuf_pkt_len(m) ((m)->pkt_len)
1427 * A macro that returns the length of the segment.
1429 * The value can be read or assigned.
1434 #define rte_pktmbuf_data_len(m) ((m)->data_len)
1437 * Prepend len bytes to an mbuf data area.
1439 * Returns a pointer to the new
1440 * data start address. If there is not enough headroom in the first
1441 * segment, the function will return NULL, without modifying the mbuf.
1446 * The amount of data to prepend (in bytes).
1448 * A pointer to the start of the newly prepended data, or
1449 * NULL if there is not enough headroom space in the first segment
1451 static inline char *rte_pktmbuf_prepend(struct rte_mbuf *m,
1454 __rte_mbuf_sanity_check(m, 1);
1456 if (unlikely(len > rte_pktmbuf_headroom(m)))
1459 /* NB: elaborating the subtraction like this instead of using
1460 * -= allows us to ensure the result type is uint16_t
1461 * avoiding compiler warnings on gcc 8.1 at least */
1462 m->data_off = (uint16_t)(m->data_off - len);
1463 m->data_len = (uint16_t)(m->data_len + len);
1464 m->pkt_len = (m->pkt_len + len);
1466 return (char *)m->buf_addr + m->data_off;
1470 * Append len bytes to an mbuf.
1472 * Append len bytes to an mbuf and return a pointer to the start address
1473 * of the added data. If there is not enough tailroom in the last
1474 * segment, the function will return NULL, without modifying the mbuf.
1479 * The amount of data to append (in bytes).
1481 * A pointer to the start of the newly appended data, or
1482 * NULL if there is not enough tailroom space in the last segment
1484 static inline char *rte_pktmbuf_append(struct rte_mbuf *m, uint16_t len)
1487 struct rte_mbuf *m_last;
1489 __rte_mbuf_sanity_check(m, 1);
1491 m_last = rte_pktmbuf_lastseg(m);
1492 if (unlikely(len > rte_pktmbuf_tailroom(m_last)))
1495 tail = (char *)m_last->buf_addr + m_last->data_off + m_last->data_len;
1496 m_last->data_len = (uint16_t)(m_last->data_len + len);
1497 m->pkt_len = (m->pkt_len + len);
1498 return (char*) tail;
1502 * Remove len bytes at the beginning of an mbuf.
1504 * Returns a pointer to the start address of the new data area. If the
1505 * length is greater than the length of the first segment, then the
1506 * function will fail and return NULL, without modifying the mbuf.
1511 * The amount of data to remove (in bytes).
1513 * A pointer to the new start of the data.
1515 static inline char *rte_pktmbuf_adj(struct rte_mbuf *m, uint16_t len)
1517 __rte_mbuf_sanity_check(m, 1);
1519 if (unlikely(len > m->data_len))
1522 /* NB: elaborating the addition like this instead of using
1523 * += allows us to ensure the result type is uint16_t
1524 * avoiding compiler warnings on gcc 8.1 at least */
1525 m->data_len = (uint16_t)(m->data_len - len);
1526 m->data_off = (uint16_t)(m->data_off + len);
1527 m->pkt_len = (m->pkt_len - len);
1528 return (char *)m->buf_addr + m->data_off;
1532 * Remove len bytes of data at the end of the mbuf.
1534 * If the length is greater than the length of the last segment, the
1535 * function will fail and return -1 without modifying the mbuf.
1540 * The amount of data to remove (in bytes).
1545 static inline int rte_pktmbuf_trim(struct rte_mbuf *m, uint16_t len)
1547 struct rte_mbuf *m_last;
1549 __rte_mbuf_sanity_check(m, 1);
1551 m_last = rte_pktmbuf_lastseg(m);
1552 if (unlikely(len > m_last->data_len))
1555 m_last->data_len = (uint16_t)(m_last->data_len - len);
1556 m->pkt_len = (m->pkt_len - len);
1561 * Test if mbuf data is contiguous.
1566 * - 1, if all data is contiguous (one segment).
1567 * - 0, if there is several segments.
1569 static inline int rte_pktmbuf_is_contiguous(const struct rte_mbuf *m)
1571 __rte_mbuf_sanity_check(m, 1);
1572 return !!(m->nb_segs == 1);
1576 * @internal used by rte_pktmbuf_read().
1578 const void *__rte_pktmbuf_read(const struct rte_mbuf *m, uint32_t off,
1579 uint32_t len, void *buf);
1582 * Read len data bytes in a mbuf at specified offset.
1584 * If the data is contiguous, return the pointer in the mbuf data, else
1585 * copy the data in the buffer provided by the user and return its
1589 * The pointer to the mbuf.
1591 * The offset of the data in the mbuf.
1593 * The amount of bytes to read.
1595 * The buffer where data is copied if it is not contigous in mbuf
1596 * data. Its length should be at least equal to the len parameter.
1598 * The pointer to the data, either in the mbuf if it is contiguous,
1599 * or in the user buffer. If mbuf is too small, NULL is returned.
1601 static inline const void *rte_pktmbuf_read(const struct rte_mbuf *m,
1602 uint32_t off, uint32_t len, void *buf)
1604 if (likely(off + len <= rte_pktmbuf_data_len(m)))
1605 return rte_pktmbuf_mtod_offset(m, char *, off);
1607 return __rte_pktmbuf_read(m, off, len, buf);
1611 * Chain an mbuf to another, thereby creating a segmented packet.
1613 * Note: The implementation will do a linear walk over the segments to find
1614 * the tail entry. For cases when there are many segments, it's better to
1615 * chain the entries manually.
1618 * The head of the mbuf chain (the first packet)
1620 * The mbuf to put last in the chain
1624 * - -EOVERFLOW, if the chain is full (256 entries)
1626 static inline int rte_pktmbuf_chain(struct rte_mbuf *head, struct rte_mbuf *tail)
1628 struct rte_mbuf *cur_tail;
1630 /* Check for number-of-segments-overflow */
1631 if (head->nb_segs + tail->nb_segs >= 1 << (sizeof(head->nb_segs) * 8))
1634 /* Chain 'tail' onto the old tail */
1635 cur_tail = rte_pktmbuf_lastseg(head);
1636 cur_tail->next = tail;
1638 /* accumulate number of segments and total length.
1639 * NB: elaborating the addition like this instead of using
1640 * -= allows us to ensure the result type is uint16_t
1641 * avoiding compiler warnings on gcc 8.1 at least */
1642 head->nb_segs = (uint8_t)(head->nb_segs + tail->nb_segs);
1643 head->pkt_len += tail->pkt_len;
1645 /* pkt_len is only set in the head */
1646 tail->pkt_len = tail->data_len;
1652 * Dump an mbuf structure to a file.
1654 * Dump all fields for the given packet mbuf and all its associated
1655 * segments (in the case of a chained buffer).
1658 * A pointer to a file for output
1662 * If dump_len != 0, also dump the "dump_len" first data bytes of
1665 void rte_pktmbuf_dump(FILE *f, const struct rte_mbuf *m, unsigned dump_len);
1671 #endif /* _RTE_MBUF_H_ */